Pickup trucks generally include a loading bed and a pair of lateral walls. A tailgate is pivotally mounted between the lateral walls and has an edge which lies adjacent to the loading bed. Conventional tailgates are swingable between a vertical closed and a horizontal opened position about the pivots.
When the tailgate is secured in the vertical closed position, articles are generally confined on the loading bed between the lateral walls, the cabin of the pickup truck, and the tailgate. In that position, the pickup truck as a whole presents more drag when travelling through and displacing ambient air at a given vehicle speed than if the tailgate is positioned in the horizontal opened position. This is because, as the pickup truck travels through ambient air, displaced air may flow downwardly and inwardly from the lateral walls of the cargo hold with significant impedance by the closed tailgate.
In general, the need has arisen for an air-permeable tailgate which would serve to constrain loads mounted in the cargo hold, while offering a reduced, aerodynamically efficient drag profile. Such approaches are exemplified by U.S. Pat. No. 4,353,589 which issued on Oct. 12, 1982. That reference discloses an air permeable closure assembly wherein the tailgate takes the form of an opened grid which permits the free flow of air through the tailgate and decreases the wind resistance of the vehicle, reduces drag, increases mileage, and allows rearward freedom of vision. Another approach is exemplified by U.S. Pat. No. 4,861,093 which issued on Aug. 29, 1989. That reference discloses a vented tailgate for use on a pickup truck. The tailgate is provided with transversely extending louver members which define downwardly and rearwardly inclined air passageways which permit the passage of air through the tailgate.